From mboxrd@z Thu Jan 1 00:00:00 1970 From: NeilBrown Subject: Re: Can't reshape raid0 to raid10 Date: Wed, 4 Feb 2015 17:39:21 +1100 Message-ID: <20150204173921.23df9d79@notabene.brown> References: <1718053393.1731733.1419906625563.JavaMail.zimbra@redhat.com> <484995116.1735572.1419909221275.JavaMail.zimbra@redhat.com> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; boundary="Sig_/4FYTFlpOlO1yQN0ylgJf1X6"; protocol="application/pgp-signature" Return-path: In-Reply-To: <484995116.1735572.1419909221275.JavaMail.zimbra@redhat.com> Sender: linux-raid-owner@vger.kernel.org To: Xiao Ni Cc: linux-raid@vger.kernel.org List-Id: linux-raid.ids --Sig_/4FYTFlpOlO1yQN0ylgJf1X6 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable On Mon, 29 Dec 2014 22:13:41 -0500 (EST) Xiao Ni wrote: > Hi Neil >=20 > When I try to reshape a raid0 to raid10, it'll fail like this: >=20 > [root@dhcp-12-133 mdadm-3.3.2]# lsblk=20 > NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT > sda 8:0 0 111.8G 0 disk=20 > =E2=94=9C=E2=94=80sda1 8:1 0 1000M 0 part /boot > =E2=94=9C=E2=94=80sda2 8:2 0 29.3G 0 part / > =E2=94=9C=E2=94=80sda3 8:3 0 512M 0 part [SWAP] > =E2=94=9C=E2=94=80sda4 8:4 0 1K 0 part=20 > =E2=94=9C=E2=94=80sda5 8:5 0 102M 0 part=20 > =E2=94=94=E2=94=80sda6 8:6 0 10.1G 0 part=20 > =E2=94=94=E2=94=80VolGroup00-LogVol00 254:0 0 9.9G 0 lvm =20 > sdb 8:16 0 111.8G 0 disk=20 > =E2=94=9C=E2=94=80sdb1 8:17 0 2G 0 part=20 > =E2=94=94=E2=94=80sdb2 8:18 0 10G 0 part=20 > sdc 8:32 0 186.3G 0 disk=20 > =E2=94=9C=E2=94=80sdc1 8:33 0 2G 0 part=20 > =E2=94=94=E2=94=80sdc2 8:34 0 10G 0 part=20 > sdd 8:48 0 111.8G 0 disk=20 > =E2=94=9C=E2=94=80sdd1 8:49 0 2G 0 part=20 > =E2=94=94=E2=94=80sdd2 8:50 0 10G 0 part=20 > [root@dhcp-12-133 mdadm-3.3.2]# mdadm -CR /dev/md0 -l0 -n3 /dev/sdb1 /dev= /sdc1 /dev/sdd1=20 > mdadm: Defaulting to version 1.2 metadata > mdadm: array /dev/md0 started. > [root@dhcp-12-133 mdadm-3.3.2]# mdadm --grow /dev/md0 -l10 -a /dev/sdb2 /= dev/sdc2 /dev/sdd2=20 > mdadm: level of /dev/md0 changed to raid10 > mdadm: add new device failed for /dev/sdb2 as 6: No space left on device >=20 > =20 > But if I reshape the raid0 to raid5, reshape raid5 to raid0, then resh= ape raid0 to raid10 use > the same command it'll succeed.=20 >=20 > [root@dhcp-12-133 mdadm-3.3.2]# mdadm -CR /dev/md0 -l0 -n3 /dev/sdb1 /dev= /sdc1 /dev/sdd1 > [root@dhcp-12-133 mdadm-3.3.2]# mdadm --grow /dev/md0 -l5 > [root@dhcp-12-133 mdadm-3.3.2]# cat /proc/mdstat=20 > Personalities : [raid6] [raid5] [raid4] [raid0] [raid10]=20 > md0 : active raid5 sdd1[2] sdc1[1] sdb1[0] > 6285312 blocks super 1.2 level 5, 512k chunk, algorithm 2 [4/3] [UU= U_] > =20 > unused devices: >=20 > [root@dhcp-12-133 mdadm-3.3.2]# mdadm --grow /dev/md0 -l0 > [root@dhcp-12-133 mdadm-3.3.2]# cat /proc/mdstat=20 > Personalities : [raid6] [raid5] [raid4] [raid0] [raid10]=20 > md0 : active raid0 sdd1[2] sdc1[1] sdb1[0] > 6285312 blocks super 1.2 512k chunks > =20 > unused devices: > [root@dhcp-12-133 mdadm-3.3.2]# mdadm --grow /dev/md0 -l10 -a /dev/sdb2 /= dev/sdc2 /dev/sdd2=20 > mdadm: level of /dev/md0 changed to raid10 > mdadm: added /dev/sdb2 > mdadm: added /dev/sdc2 > mdadm: added /dev/sdd2 >=20 > So I guess it's the problem add the disk to raid10 after the reshapin= g. In the function > super_1_validate, it'll set the mddev->dev_sectors using the superblock = read from disks.=20 > If it's raid0, the le64_to_cpu(sb-size) is 0. So when add disk to raid10 = bind_rdev_to_array > return -ENOSPC. >=20 > When create raid0, it doesn't write give the value to s->size. So the= sb-size is 0. > I modify the code about Create.c. I'm not sure whether it's right to do s= o. But it can resolve=20 > the problem. Thanks for the report. I think this need to be fixing in the md driver, when the reshape happens. Something like the following. NeilBrown diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c index d1203cddb024..b8d76b1fba64 100644 --- a/drivers/md/raid10.c +++ b/drivers/md/raid10.c @@ -3872,7 +3872,7 @@ static int raid10_resize(struct mddev *mddev, sector_= t sectors) return 0; } =20 -static void *raid10_takeover_raid0(struct mddev *mddev) +static void *raid10_takeover_raid0(struct mddev *mddev, sector_t size, int= devs) { struct md_rdev *rdev; struct r10conf *conf; @@ -3882,6 +3882,7 @@ static void *raid10_takeover_raid0(struct mddev *mdde= v) mdname(mddev)); return ERR_PTR(-EINVAL); } + sector_div(size, devs); =20 /* Set new parameters */ mddev->new_level =3D 10; @@ -3892,12 +3893,15 @@ static void *raid10_takeover_raid0(struct mddev *md= dev) mddev->raid_disks *=3D 2; /* make sure it will be not marked as dirty */ mddev->recovery_cp =3D MaxSector; + mddev->dev_sectors =3D size; =20 conf =3D setup_conf(mddev); if (!IS_ERR(conf)) { rdev_for_each(rdev, mddev) - if (rdev->raid_disk >=3D 0) + if (rdev->raid_disk >=3D 0) { rdev->new_raid_disk =3D rdev->raid_disk * 2; + rdev->sectors =3D size; + } conf->barrier =3D 1; } =20 @@ -3920,7 +3924,9 @@ static void *raid10_takeover(struct mddev *mddev) mdname(mddev)); return ERR_PTR(-EINVAL); } - return raid10_takeover_raid0(mddev); + return raid10_takeover_raid0(mddev, + raid0_conf->strip_zone->zone_end, + raid0_conf->strip_zone->nb_dev); } return ERR_PTR(-EINVAL); } --Sig_/4FYTFlpOlO1yQN0ylgJf1X6 Content-Type: application/pgp-signature Content-Description: OpenPGP digital signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v2 iQIVAwUBVNG+mTnsnt1WYoG5AQJ+GQ/+OBdMILyorn6wxhNROXKl765ifTC7il/G 3nrutS6ngXcSvb3YG5Gdh9evr0+RY6wLLLRHFIY7y2JP192RGIwjMaWudp/FYly4 LiVByDHJgpAkEtwomzxmq8n4nP1MaEhOyEY8qFRDYgYz5eDrNRet3QEUurXgTJDe 72kXcpNDYmRlsz4fH745KxekfQdQ/+z4ps85albAncfaxtOcEJdDeQhBQxhYm4ct gf9V/HMFm1nCtP2CYZPvCM4ExN5q0L9u8mrqaMi3iMdpJdZmkFRZzM2/+YDJczOC e6aW78bUFxXYkQUGrz+ypCtAPd5mQOVG+hPu27A7ZDhQAeXXE0SaR94rkcZWNL9K WcQHh1qEDgb2LSwZZ1J+MUnI+f6YUfNym0KNh28mQUqshT8i8kPM8hHWjOB8YQkt yBEofo5UxVGqhdhyVgsGXq5NLB0Dwtay3VUUKByyKQu345XC5ZaAL9JDlQaY4vlf hNmBaXsDaqZWisJ2+xw1g49dLjq9rFw7ryKpv0CpIu1yD7wxfsi/GMw/qTNEnk41 k+q172Yc2Q8xzuBNKT+s7d62ByfGjQq3wf5P3ThwvMoHh1F54J5NUTXn3TLtpR0Y YgTMuBn4ySI9++BNmyu6PiYenxvK1DmheRDmvjFB88Jd+BXPoC2Zibzq4Xzw58tp HRyoo57qwjI= =9Ma/ -----END PGP SIGNATURE----- --Sig_/4FYTFlpOlO1yQN0ylgJf1X6--